Improved screw-wrench



UNITED STATES PATENT OFFICE.

F. I-IOLLEN AND A. H. PIERCE, OF BLAIRSVILLE, PENNSYLVANIA.

yuvlPRovED SCREW-WRENCH.

Specification forming part of Letters Patent No. 34,498, dated February 25,1862.

.To all whom t may concern:

Be it known that We, F. HOLLEN and A. I-I. PIERCE, both of Blairsville, in the county of Indiana and State of Pennsylvania, have invented a new and Improved Screw-Vrench; and we do hereby declare that the following is a full, clear, and exact description of the same, reference being had to the accompanying drawings, forming a part of this speciiication, in which- Figure 1 represents a side elevation of our invention when the same is closed. Fig. 2 is a similar elevation of the same when it is opened and applied to a burr or nut.

Similar letters of reference indicate corresponding parts in the two figures.

This invention consists in giving to theinner surfaces of two jawsv theforrn of racks with ratchet-teeth pointing in opposite directions, said jaws being connected by means of a hinge-joint and forced together by a suitable spring in such a manner that a wrench is obtained which can be applied to burrs or small nuts of various sizes, and which can be operatedl with easeland facility.

To enable those skilled in the art to make and use our invention, we will proceed to describe it with reference to the drawings.

The two jaws A A are connected by a hingejoint a, and they are bent at an angle of about twenty degrees (more or less) to facilitate the operation. Each of the jaws is provided on its inner surface with a toothed rack b b', the teeth beingshaped like ratchetteeth, and so arranged in vrelation to each other that when the jaws are closed, as shown in Fig. 1, the teeth of one jaw fit into the notches between the teeth of the other jaw. By referring to the drawings it will be seen that the teeth b of the stationary jaw A point outward away from the joint a, whereas the teeth b of the movable jaw A point toward the joint.

The shank c of the stationary jaw A is inserted into the handle B, and the shank c of the movable jaw extends also beyond the hinge-joint, and it is bent upward or away from the shank c of the stationary jaw, so that by closing up the shanks c c the jaws A A are thrown open, and vice Versa. A spring C, which is inserted between the shauks c c', keeps the jaws closed.

The operation is a follows: When the jaws A A are thrown open, one of the teeth b* of the stationary jaw anda corresponding tooth 22'* of the movable jaw can be brought to bear on the edges of a burr in the manner as clearly shown in Fig. 2 of the drawings, where the burr is represented in red outlines. It will be noticed that in. this position the vertical sides of the teeth b* b* are applied to the edges of the burr, and by moving the handle in the direction of the arrow marked upon itin Fig. 2 the burr is turned in the direction of the arrow marked thereon. It in turning the burr the handle or shank of the wrench meets with a resistance, it is not necessary to take the wrench off from the burr in order to take afresh hold. By depressing the shank of the movable jaw the latter is thrown open and the wrench can be moved back for a fresh hold. It is obvious that by turning the wrench upside down it allows of turning the burr in the direction opposite to the arrow marked on it in Fig. 2.

For burrs or nuts of different size different teeth of the jaws will be brought in opera- A burr-wrench with two jaws A A', the inv ner surfaces of which are provided with ratchet-teeth b b', and which are united bya hinge-joint et and forced together by a suitable spring C, in the manner and for the purpose shown and described.

F. I-IOLLEN. A. I-I. PIERCE. Vitnesses:

A. B. BARRETT, JOHN M. CHASE. 

